New technique for measuring ferroelectric and antiferroelectric hysteresis loops

A new technique, the double-wave method (DWM), is developed to refine ferroelectric D-E hysteresis loops. The method discriminates non-hysteresis components from ferroelectric D-E hysteresis loops by applying identical unipolar waves twice. It extracts only the hysteresis component automatically without any assumptions. The DWM can compensate intricate non-hysteresis components in D-E loops which traditional methods cannot. It can separate an antiferroelectric component from ferroelectric and other components by applying a bias electric field. As a typical example of a ferroelectric, D-E loops of NaNO₂ by the DWM are examined. To demonstrate the advantages of the DWM, D-E loops of multiferroic ErMn₂O₅ are presented. Antiferroelectric-like components in D-E loops are separated and fine ferroelectric loops of ErMn₂O₅ are observed by the DWM.